The present invention relates to machines for forming cylindrical bales of crop material, such as hay, and particularly to an improved means of applying a fluid preservative, such as liquid ammonia, to the crop material as the bale is being formed.
The potential benefits of applying preservatives to hay either during a baling process or to the finished bale are well known and include (a) permitting the hay to be baled and stored at higher moisture contents without spoilage, thus reducing field losses and making the hay making operation less dependent on favorable weather conditions; (b) improved palatability and digestibility; and (c) higher nutrient content. The relative importance of these benefits varies with the crop being treated and the preservative used.
However, for best results and acceptable cost, the preservative must be uniformly distributed through the crop material and applied with a minimum of wastage. The method of localized injection of preservative into finished bales is known to be inadequate but some success has been achieved with conventional rectangular balers having apparatus for injecting a fluid preservative into the mass of hay as it is being compacted in the baling chamber.
It is also known to spray the windrow immediately ahead of the pickup of both rectangular and big round balers. But when a fixed spray pattern width is used with a typical windrow varying in both width and thickness, there will clearly be wastage (when for example the windrow width is narrow) and an effective variation in rate of application due to variation in windrow thickness. And, of course, apart from the direct loss of fluid failing to contact the crop material, in the case of a volatile fluid such as liquid ammonia, there will be additional losses to the atmosphere through vaporization both before the ammonia reaches the crop material and from the crop material surfaces while it is still enroute to the baling chamber. With a fluid such as ammonia, such losses are not only costly but may be offensive to an operator.